Sand and gravel cleaning machine



(No Model) 4 Sheets-Sheet 1..

P. J. HOYT. SAND AND GRAVEL CLEANING MACHINE. No. 449,417. Patented Mar. 31,1891.

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(No Model.)

4 Sheets-Sheet 2. P. J. HOYT. SAND AND GRAVBL CLEANING MACHINE. No. 449,417.

Patented Mar. 31, 1891.

i ll i i. I I I BY I W.

ATTORNEY,

(No Model.) 4 Sheets-Sheet 3.7

P. ,J. HOYT. SAND AND GRAVEL GLEANING MACHINE.

No. 449,417. Patented Mar. 31,1891.

ATTORNEY)! (No Model.) 4 Sheets-Sheet 4.

P. J. HOYT. SAND AND GRAVEL CLEANING MACHINE. No. 449,417. Patented Mar. 81, 1891.

WITNESSES. I IVEIVT f? ATTORNEY.

UNITED STATES PATENT OFFICE.

FRED J. HOYT, OF CHICAGO, ILLINOIS.

SAND AND GRAVEL CLEANING MACHINE.

SPECIFICATION forming part of Letters Patent No. 449,417, dated March 31, 1891.

Application filed July 23, 1890. Serial No. 359,612. (No model) To all whom it may concern.-

Be it known that I, FRED J. HOYT, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Sand and Gravel Cleaning and Assorting Machines; and I do hereby declare the followingto be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to screens for wash- 1 ing, cleaning, and asserting into different grades sand, gravel, coal, coal-slack, ores, and other materials.

It consists, generally, of an apparatus comprising two or more screens of varying degrees of fineness arranged horizontally on a vertical revolving axis, each screen having at its periphery a trough into which the coarser part of the material is thrown by centrifugal action, while the finer material passes through to the next finer screen below, each of said troughs provided with a water-inlet and a discharge-spout, to which the trough inclines, and out of which spout the material is forced by the action of the water, and finally of a bottom solid disk which discharges all of the remaining finest sifted material. These and other parts, singly and in combination, and their construction and operation are hereinafter more particularly described and claimed.

My invention is illustrated in the accompanying drawings, in which- Figure 1 is a vertical section; Fig. 2, a plan; Fig. 3, a side view in elevation, and Fig. 4 a modification in the arrangement of the apparatus.

Referring to the drawings, A is a cylindrical metal casin g built up of sections a b 0 cl, each provided with a flange e, which flanges are bolted together. These sections, which are preferably of cast-iron, are in practice each made about sixteen inches in height and six feet in diameter, and are further united and strengthened by posts 0, having a thickness equal to the width of the flanges e. A sheet-steel lining is riveted to these posts. In a structure of the above-given dimensions and placing the posts twelve inches apart about sixteen posts would be employed with each cylinder. The cylinder A thus composed of sections is supported on legs secured to a bottom spider-frame B.

The apparatus is provided internally with a series of troughs D, a trough to each cylinder. These troughs are composed, preferably, of sheet-steel with an inner vertical wall f and a floor g. They are secured to each section of the casing by means of anglebraces H. These braces are composed of a vertical part extending up the side of the trough,a horizontal part h under and against the bottom of the trough, and a vertical foot 7?, extending against the inner wall of a section. The trough is riveted to these braces through its side and bottom, and each foot of the brace is bolted through the wall of the section to a post 0.

I isawater-inlet pipe, say, one and one-half inch in diameter, and divided as it enters the trough by a Tintotwo three-fourths-inch pipes, which are turned and discharged in opposite directions. It will be now noticed that the floor of the trough is inclined on both sides from these inlet-pipes to a large discharge-spout K, located at a lower point on the opposite side of the same section. The trough for this reason has its wall f of gradually-increasing height from the water-inlet to the discharge-spout. The trough thus constructed constitutes a channel, or it may be regarded as two opposite channels, say, four inches wide and twelve inches deeper at the point of discharge than where the water enters. The trough may also be lined on sides and bottom with sheet-steel, or it maybe cast in one piece, or each section of the apparatus, with or without the trough, may be so cast.

L is a central revolving shaft having its lower bearing in a box 1 at the center of the spider-frame B and its upper bearing in a box Z on the lid or cover A. Said cover is provided with a flange a which is screwed to the flange of the top section, and is also provided with a spout or hopper A through which material is fed into the apparatus.

M is a band-pulley secured on the shaft L near its lower end beneath the cylinder A. O P Q R are a series of disk screens placed therein. 0, the lowest disk, has a solid bot tom concave on its under side and convex on top. The other disks P Q R are perforated and may be flat on both sides, or, if desired, slightly concave on the upper side to retard, if necessary, the centrifugal action in throwing off the coarser material into the trough. Each disk is composed of a round sheet of metal bounded by a solid rim 3 and screwed through said rim to an under ring 15. The ring is cast with six arms 25 to a central hub '12. The rim 5 extends beyond the ring 2, so

that when each disk is in place the rim willcxtend over the edge of the vertical wall fof the trough in order that the material thrown over the edge of the screen will fall fairly onto the bed of the trough. These disk screens are put in place on the central shaft, beginning with the bottom one, by sliding the hub onto the shaft and then by means of a set-screw to, securing each disk to the shaft a little above a trough, so that it will not come in contact therewith.

I have shown three of the perforated screens and one bottom solid disk; but a greater or less number of screens may be employed.

The perforated screens increase in fineness of perforations from top to bottom.

The operation of my device will be readily perceived. The machine is operated through the band-pulley by any suitable power. The material is introduced through the hopper at the top and falls onto the top screen having the coarser perforations. The finest particles are carried through the screen and fall on the one below. The material too large to pass through the perforations is thrown by centrifugal force over the edge of the screen into the inclined channel or channels of the trough, where it is met by the strong streams of water and carried forward thereby to and out of the discharge-spout, at the same time being thoroughly washed. Here the cleansed material is received on a platform or other place and the water conducted off and away therefrom. This process is the same in each section and with each screen until the bottom one is reached, which is constructed, as above described, with a solid bottom and its upper face convex, and all the material left, which is the finest, is carried into the trough, washed, and forced out of the bottom spout. The material thus operated on is all washed, assorted, and delivered in different grades. In mixed sand and gravel, forinstance,thclargest stones and gravel are discharged from the top spout, the medium-sized gravel from the next, what is known as torpedo gravel from the next, and the finest sand from the bottom, and all in a washed and cleaned condition.

The number of screens, the coarseness or fineness of the perforations, and the character of the surface of the screens as to convexity or concavity can all be varied to suit the nature of the material operated on.

On Sheet 4: a modification in the arrangement of the apparatus is illustrated. Three cylinders are there shown arranged at different elevations; but each cylinder has but two sections and two disks, one perforated and one closed. by each section into but two grades, and when discharged from the bottom disk and spout of one section is passed on to the second section and from that to the third. This or a similar arrangement permits the material of the different grades to be carried to greater distances and to receptacles located more widely apart than when the operation is confined to a single apparatus.

In operating on some materials which it is not necessary or desirable to wash the supply of water to the trough can be stopped, and,i f the material is not too heavy, can be forced out of the troughs and discharge-spouts by strong currents of air introduced in place of the currents of water, or theincline of the trough may be made great enough to discharge the material withont other force. The water may be carried into the trough'by two pipes instead of a divided one, as shown, and may be forced in by aid of pumps.

\Vhat I claim is-- 1. In a screening apparatus, the closed cylindrical casing composed of two or more separate sections of metal detachably secured together, in combination with a trough secured to the inner wall of said cylinder, the trough having an inclined floor and an inner vertical wall, a water-inlet at the highest point of said trough for discharging water both ways into the inclines of the trough, a disk screen held above and extending slightly beyond the edge of the said wall of the trough, a vertical rotary shaft to which said screen is attached, and a discharge-spout at the lowest point of said trough, substantially as described.

2. In a screening apparatus composed of a cylinder built of separate and detachable sections, in combination with a horizontal revolving screen, an inclined stationary doublechanneled trough provided with an inner vertical wall surrounding said screen and secured to the inner wall of the cylinder, a dischargespont, and a water inlet or inlets discharging The material is thus separated IOC IIO

water in opposite directions into said trough or channel, whereby material falling from the screen into said trough is washed and carried out by thewater, substantially as described. 3. A screening apparatus composed of a cylinder built of separate and detachable sections, each section provided with an inclined trough composed of a channel on each side thereof, said trough with its double channel rigidlysecured to and running entirely around its inner wall, in combination with an inlet and a discharge-spout and a revolving screen for each section, substantially as described.

4. In a screening apparatus, the combination, with a closed cylinder built up in separate detachable sections, of horizontal screens, a central vertical rotating axis to which said screens are secured, said screens increasing in fineness of mesh from top to bottom, abettom-closed disk to receive the finest sifted material, said cylinder provided with a screen and disk separately and detachably secured to said axis, a hopper through the top of the cylinder to receive the material to be screened, and a discharge-spout at the bottom of each section of said cylinder, substantially as described.

5. A cylindrical screen-casing built up in sections, which sections are each provided with a flange on its outer edge, by which they are secured together, said casing mounted on legs, and a spidenfranie to which said legs are secured, in combination with a Vertical rotating axis, horizontal rotary disk screens secured thereto, and a bottom-closed disk also secured to said axis, and a discharge-spout leading from said bottom disk, substantially as de scribed.

In testimony whereof I affix my signature in presence of two witnesses.

FRED J. IIOYT.

Witnesses:

WM. H. CHANDLER, W. G. DOOLITTLE. 

